SONE-439 My kind and proud tall girlfriend was seduced by the swimming club advisor's sex instruction.

No matter what I did, I was a bullied boy, and the one who saved me was Mitsuha Asuha, a senior in the swimming club whom I admired. I was happy just to have recognized my existence. I was happy just to have had a brief conversation. It's free to say. I just have to tell her how I feel... I mustered up the courage to tell her how I liked her, and I don't know what struck me, but I got an unexpected reply: "Okay, with you." I was prepared to be single for the rest of my life, but now I have a girlfriend. Will I kiss her or have sex with her from now on? It doesn't matter when that happens. Someday... That's what I thought, but the evil hand of the advisor was creeping up on me without my knowledge.